Humans who work behind a computer screen have an undesirable tendency of maintaining a static body posture for a prolonged period of time. This typically results in stiffness in the neck and shoulders. It is noted that even maintaining a correct body posture has negative effects for people working with computers when the same body posture is maintained for a prolonged period of time. Frequent small changes in the body posture are recommended when performing computer screen work for prolonged periods of time, thereby preventing Repetitive Strain Injuries (RSI). The small changes in body posture are referred to as motility.
In addition, from ergonomic research, it is known that having the proper viewing angle is essential in minimizing vision and musculoskeletal disorders. From observations, it is known that many people have their monitor at too high of a position. This is partly because people sit upright during monitor placement and sink back in their chairs during actual use, and partly because users think they have the right monitor placement, but they lack knowledge on this subject or measure inaccurately. This problem is generally solved by coaching users in and reinforcing proper positioning during regular use. However, such coaching is generally incomplete because users tend to have an inaccurate understanding of their viewing distance or viewing angle relative to the computer display.
Various devices for inducing motility are known. One example is a product called the Kinetic-XS (see http://www.kinetic-xs.nl), which discloses a motorized adapter that is disposed between a computer display and a supporting arm to the display. The adapter creates a very slow rotation (2 degrees at 0.4 Hz) of the display unit in the sagittal plane of the user around an axis located in the center of mass of the computer display. Because of the rotation of the display, a person sitting in front of the display has increased movements of the head, and thus an increase in cervical motion. However, the disadvantage to such a solution is the rotation of an entire computer display, which requires a motorized adapter.
There are other ways of monitoring the motility of a computer screen worker such as by using pressure sensors in the seat of the office chair, but these solutions are not simple and low cost.
However, a significant drawback of the existing means or programs that coach a user to change behavior is that such means or programs typically interrupt a user or require a user to switch to a different mode other than an existing mode of operation. For example, users get a pop-up screen and are typically unable to continue their respective work until they have “clicked away” the screen. For applications that coach the user to work more ergonomically, to prevent RSI, or to stimulate motility, a different kind of feedback is desired.